Yield and yield components of CIP advanced potato clones under Rwandan agro-ecologies

Abstract

Objective: To evaluate the yield performance of new potato clones under Rwanda climatic conditions in attempt for developing new potato varieties with market lead traits, that can replace the existing having more than 20 years old. Methodology and Results: the Potato Sub-Program of Rwanda agriculture and Animal Resources Development board (RAB) in collaboration with the International Potato Center (CIP), has introduced and evaluated the yield performance of six advanced potato clones(CIP388676.1, CIP392657.8, CIP398190.89, CIP392797.22, CIP398193.511, and CIP394611.112), in comparison with most popular local varieties (Kinigi and Kirundo)under Rwanda climatic conditions. Trials were established at Kinini, Rwerere, and Tamira RAB Research Station located in a randomized complete block design with three replications for two growing seasons. The analysis of variance revealed high significant effects (p-value < 0.01) of genotype, site, season, genotype x site, and site x season on total tuber yields. A positive correlation of 90% was observed between number of tuber per plant and yield of no marketable roots. Across sites and seasons genotypes showed variation in the performance. The high average yields of 47.08 and 54.58 t/ha were observed at Rwerere, in season 2017B and season 2018A, respectively. The Kinigi site had tuber yields of 32.02 and 36.44 t/ha, while Tamira site has 20.25 and 35.71 t/ha for season 2017B and season 2018A, respectively. The Rwerere site revealed a high dry matter content compare to other sites. The dry matter was 22.18, 19.34 and 18.74% of tuber fresh weight for Rwerere, Kinigi and Tamira, respectively. At each site, the genotype CIP 394611.112 revealed the highest dry matter content, this dry matter content was 20.67, 25.95 and 20.78 % of tuber fresh weight at Kinigi, Rwerere and Tamira. This dry matter was higher than the dry matter content of local check Kinigi with 18.05, 21.42, and 19.11 %, and Kirundo with 16.69, 21.88 and 15.6% of tuber fresh weight at Kinigi, Rwerere, and Tamira respectively. The genotype CIP392657.8, CIP392797.22, CIP398190.89, Kinigi and Kirundo had marketable yields that are above 30 t/ha, while genotypes such as CIP388676.1, CIP394611.112 and CIP398193.511 revealed marketable yield which was below 27.5 t/ha. Conclusion and Application of results: The clones CIP392657.8, CIP392797.22, and CIP398190.89 which showed the yields comparable to local checks are candidate for new potato varieties in Rwanda. The release of these new potato varieties will increase the number of approved varieties and farmers choices to diversify the potato production. Keywords: Clone, performance, potato, yields